“As those with experience of it know, depression doesn’t just drop in and say a quick hello and head for the hills. Or, at least my kind didn’t.

“No, it took a fancy to me, and decided to take up residence for a few months, and boy, did it make its presence felt.

“Especially in the mornings when the day ahead became something to endure, rather than enjoy.”

RTE bosses supported the star during his time off the air promising him his job was safe, while Miriam O’Callaghan stepped into the morning slot.

And John revealed that his listeners particularly helped him get through his extremely tough depression battle – with a bag of mail waiting for him when he first returned to Montrose last week.

He added: “In my battle to get better, I discovered that I had in my arsenal, a secret weapon - you, the listener.

“I’m so, so grateful to everyone who took the trouble to write to me, send me get well soon cards and mass cards, those of you who rang, and texted and emailed the show enquiring after my health.

“All the people I’ve met over the last few months in Rathfarnham and Borris and elsewhere, thanks for making the tougher days a bit easier with your love and concern, and for helping me get back here this morning.

“And so we can renew our friendship now and have a bit of craic in the process.”

John thanked fans for their support during his absence

And John told listeners that he wanted others facing a similar depression battle to know that they haven’t failed and shouldn’t suffer in silence.

He added: “I’m a little bit reluctant about giving advice to others who might find themselves depressed or anxious. Everyone is different.

“But one thing I will say is, don’t be too hard on yourself. You haven’t failed life’s test, share your thoughts and feelings with others and don’t suffer in silence.

“And can I say, finally, to anyone who knows anyone who’s depressed - don’t be afraid to contact them - they mightn’t reply immediately, or at all.

“But boy will they appreciate that someone is thinking of them. I know I did.”

John added that he wouldn’t have got through his battle without wife Miriam Donohoe or his kids Stephen and Catherine.

And Miriam, who he has been married to for 25 years, wrote on Twitter that she was overwhelmed by the good wishes that came flooding in from listeners.

She said: “Thanks to you all for the love and good wishes to John and our family over last six months. Depression can be fought together. Proud wife.

“To anyone out there with a family member suffering from depression - just be there for them, listen, do lots of walks, and know it will pass.”

Following his extremely open admission, fans took to Twitter to praise the host for telling all.

And Miriam O’Callaghan, who filled in for John, said: “That was a majestic tour de force by John this morn- brave, honest and incredibly moving about his absence and then just a great show.”

His first guest, comedian Pat Shortt summed up the feeling when he told John: “Great to hear you back. You’re like the clown in the circus. When the clown left the circus, everyone said no-one will ever fill his shoes.”

Previously, John had been left a nervous wreck during his time on The Business Show when doctors took him off a “super drug” for his arthritis.

He told earlier this year how it lead to him being diagnosed with a general anxiety disorder and unable to work for five months in 2007.

He said: “During that period I thought I’d never work again because of nerves. Your ability to go on air when the red light goes on. I thought, ‘How am I going to do it? I’m f*****g shaking.’

“This is what would happen. I’d be sitting here talking to someone and I’d have a panic attack. Something would come into my head and then - waaahh!

“So at the end of the five months I was back at work having been diagnosed and treated. The symptoms went and, touch wood, haven’t come back and the arthritis seemed to have burned itself out.”